Sign up to receive free email alerts when patent applications with chosen keywords are publishedSIGN UP

Abstract:

The disclosure relates to revision hip surgery or total hip arthroplasty
situations in which it is difficult for a surgeon to secure or fix an
acetabular cup or shell to the bone due, for whatever reason, to bone
loss or other bone deficiency. The system may comprise a plurality of
fasteners and an acetabular cup or shell having a plurality of openings
to thereby allow the plurality of fasteners to be inserted at diverging
angles to create multiple fixation points to distribute load and secure
the shell to available bone. The system may also include a bearing insert
for receiving a femoral head component and a plurality of spacers for
creating a cement mantle.

Claims:

1. A system for securing an orthopedic implant to a bone, comprising: a
shell comprising a central axis, an inner surface, an outer surface and a
plurality of openings formed therethrough, wherein the shell comprises a
spatial concentration of openings in a range of about five to about
fifteen openings per concentration area of said shell, wherein said
concentration area is a surface area of said outer surface of said shell
that is between a range of about eighty square millimeters to about
one-hundred and seventy-five square millimeters; a plurality of first
fasteners and a plurality of second fasteners, wherein each of the first
fasteners has a diameter of that is greater than or equal to 6.0
millimeters wherein each of the plurality of second fasteners has a
diameter that is less than or equal to 3.5 millimeters for securing said
shell to bone tissue; wherein each of the plurality of second fasteners
comprises a length that is less than thirty millimeters; wherein each of
the plurality of first fasteners and the plurality of second fasteners is
insertable through one of the openings of said shell and into the bone at
an angle with respect to the central axis of said shell, thereby
distributing and transferring forces placed on said shell to the bone at
multiple, varying insertion points, which correspond with the fastener
inserted into the bone.

2. The system of claim 1, wherein the spatial concentration of openings
per concentration area is distributed across the entire surface area of
the outer surface of the shell.

3. The system of claim 1, wherein the plurality of second fasteners
comprise at least twelve fasteners.

4. The system of claim 1, wherein the plurality of second fasteners
comprise at least fifteen fasteners.

5. The system of claim 1, wherein the plurality of second fasteners
comprise at least twenty fasteners.

6. The system of claim 1, wherein the plurality of second fasteners
comprise at least twenty-five fasteners.

7. The system of claim 1, wherein the plurality of second fasteners
comprise at least thirty fasteners.

8. The system of claim 1, wherein the plurality of second fasteners
comprise at least thirty-five fasteners.

9. The system of claim 1, wherein the plurality of second fasteners
comprise at least forty fasteners.

10. The system of claim 1, wherein the plurality of second fasteners
comprise at least forty-five fasteners.

11. The system of claim 1, wherein the plurality of second fasteners
comprise at least fifty fasteners.

12. The system of claim 1, wherein the plurality of second fasteners
comprise at least fifty-five fasteners.

13. The system of claim 1, wherein the plurality of second fasteners
comprise about fifteen fasteners to about sixty fasteners.

14. The system of claim 1, wherein each of the plurality of second
fasteners are insertable into the bone at an angle that varies and
diverges from another one of the plurality of second fasteners, such that
there is a fixation point where each of the plurality of fasteners
inserted into bone, which allows forces to be distributed and transferred
from the shell to the plurality of second fasteners inserted into the
bone at multiple, varying insertion points and from the plurality of
second fasteners to the bone itself, and wherein a length of each second
fastener is within a range of about twenty millimeters to about
twenty-five millimeters.

15. The system of claim 1, wherein the plurality of fasteners comprise an
average diameter that is between a range of about three millimeters to
about five millimeters and an average length that is between a range of
about twenty-five millimeters to about thirty-five millimeters in length.

16. The system of claim 1, wherein each of the openings comprise a
diameter that corresponds with the diameter of a corresponding fastener.

17. The system of claim 16, wherein the plurality of openings comprise an
average diameter that is same as the average diameter of the plurality of
fasteners.

18. The system of claim 1, wherein at least one of the openings is shaped
as a FIG. 8 and is defined by an overlapping circumference of two
adjacent openings.

19. The system of claim 18, wherein the shell is substantially
hemispherical, such that the FIG. 8 shaped opening in the substantially
hemispherical shell provides an ability to insert a plurality of
fasteners at different and varying angles to thereby locate said
fasteners as securely as possible in the bone, depending upon bone
anatomy, during a procedure.

20. The system of claim 1, wherein the inner surface of the shell is
textured to thereby receive a bonding agent therein.

21. The system of claim 20, wherein the texture is formed by a plurality
of troughs formed in the inner surface of the shell.

22. The system of claim 20, wherein the texture is formed by a plurality
of grooves formed in the inner surface of the shell.

23. The system of claim 1, wherein the plurality of openings in the shell
comprise a plurality of second openings, which have diameters that
correspond with the diameters of the plurality of second fasteners, such
that each of the plurality of second fasteners is insertable into each of
the plurality of second openings to assist in securing the shell to the
bone; and wherein the plurality of openings in the shell further comprise
a plurality of first openings, which have diameters that correspond with
the diameters of the plurality of first fasteners, such that each of the
plurality of first fasteners is insertable into each of the plurality of
first openings to thereby anchor the shell to the bone.

24. The system of claim 23, wherein the first openings are distributed
over the shell to target safe zones of the hip bone, and wherein said
first openings are formed at an angle with respect to the central axis of
said shell, wherein said angle is within a range of about twenty-five
degrees to about forty degrees.

25. The system of claim 23, wherein each of the second openings are
defined by a sidewall that defines a central axis of the second opening,
and wherein an acute angle is formed by the intersection of the central
axis of the second opening with a central axis of the shell.

26. The system of claim 23, wherein said second openings are formed at an
angle with respect to the central axis of said shell, wherein one or more
of the second openings are defined by a sidewall that forms an acute
angle with a line that is tangent to an exterior surface of the shell and
that intersects a central axis of the opening defined by said sidewall.

27. The system of claim 1, wherein one or more of the plurality of
openings are defined by a sidewall that forms an acute angle with a line
that is tangent to an exterior surface of the shell and that intersects a
central axis of the opening defined by said sidewall.

28. The system of claim 1, wherein one or more of the plurality of
openings are defined by a sidewall that defines a central axis of the
opening, which forms an acute angle with a line that is both tangent to
an exterior surface of the shell and that intersects said central axis of
said opening.

29. The system of claim 1, wherein one or more of the plurality of
openings are defined by a sidewall that forms an acute angle with an
imaginary line that is perpendicular to a tangent line of an exterior
surface of the shell, wherein said tangent line intersects a central axis
of the opening defined by said sidewall.

30. The system of claim 29, wherein the imaginary line is co-axial to the
central axis of the opening.

31. The system of claim 1, wherein one or more of the plurality of
openings are defined by a sidewall that defines a central axis of said
opening and that forms an acute angle with an imaginary line that is
perpendicular to a line that is both tangent to an exterior surface of
the shell and that intersects said central axis of said opening.

32. The system of claim 1, wherein one or more of the plurality of
openings are defined by a sidewall that defines a central axis of said
opening, wherein said sidewall includes a first opposing side-line and a
second opposing side-line, and wherein said first and second opposing
sidelines reside on opposing sides of the central axis of said opening
and each progresses toward said central axis of said opening in an
interior-to-exterior direction with respect to the shell.

33. The system of claim 1, wherein the system further comprises a
plurality of spacers having a head; wherein each of the spacers is sized
and shaped for insertion and securement into a vacant opening of the
shell.

34. The system of claim 33, wherein the system further comprises a
bonding agent and a bearing insert having an outer surface prepared for
receiving the bonding agent; wherein each spacer is inserted from the
inner surface of the shell into a vacant opening of said shell, such that
the head of each spacer is exposed within the inner surface of the shell
to create a mantle of the bonding agent to secure the outer surface of
the bearing insert to the inner surface of the shell.

35. The system of claim 1, wherein the system further comprises a bearing
insert and a bonding agent; wherein the spatial concentration of openings
per concentration area is distributed across the entire surface area of
the outer surface of the shell; wherein the plurality of second fasteners
comprises between about twelve fasteners and about sixty fasteners;
wherein each of the plurality of second fasteners are insertable into the
bone at an angle that varies and diverges from another one of the
plurality of second fasteners, such that there is a fixation point where
each of the plurality of fasteners inserted into bone, which allows
forces to be distributed and transferred from the shell to the plurality
of second fasteners inserted into the bone at multiple, varying insertion
points and from the plurality of second fasteners to the bone itself;
wherein a length of each second fastener is within a range of about
twenty millimeters to about twenty-five millimeters; wherein the
plurality of fasteners comprise an average diameter that is between a
range of about three millimeters to about five millimeters and an average
length that is between a range of about twenty-five millimeters to about
thirty-five millimeters in length; wherein each of the openings comprise
a diameter that corresponds with the diameter of a corresponding
fastener; wherein the plurality of openings comprise an average diameter
that is same as the average diameter of the plurality of fasteners;
wherein at least one of the openings is shaped as a figure 8 and is
defined by an overlapping circumference of two adjacent openings; wherein
the shell is substantially hemispherical, such that the figure 8 shaped
opening in the substantially hemispherical shell provides an ability to
insert a plurality of fasteners at different and varying angles to
thereby locate said fasteners as securely as possible in the bone,
depending upon bone anatomy, during a procedure; wherein the inner
surface of the shell is textured to thereby receive the bonding agent
therein; wherein the bearing insert has a prepared outer surface that is
textured to receive the bonding agent, wherein the bearing insert is
securable to the inner surface of the shell via the bonding agent;
wherein the system further comprises a plurality of spacers having a
head; wherein each of the spacers is sized and shaped for insertion and
securement into a vacant opening of the shell; and wherein each spacer is
inserted from the inner surface of the shell into a vacant opening of
said shell, such that the head of each spacer is exposed within the inner
surface of the shell to create a mantle of the bonding agent to secure
the outer surface of the bearing insert to the inner surface of the
shell.

36. A system for securing an orthopedic implant to a bone, comprising: a
bonding agent configured to attach components of the system together; a
shell comprising an outer surface configured to contact bone tissue, an
inner surface prepared with a textured finish for receiving the bonding
agent, and a plurality of openings formed between the outer surface and
the inner surface, wherein each of the openings is defined by an axis of
rotation; a plurality of fasteners, wherein each faster is insertable
through one of the openings and into bone tissue at varying, divergent
angles with respect to the axis of rotation of each opening in a splayed
manner to distribute and transfer forces placed on the shell to the bone
tissue at multiple, varying angles over a large area of the bone; and a
bearing insert having a prepared outer surface to receive the bonding
agent, wherein the bearing insert is securable to the inner surface of
the shell via the bonding agent.

37. The system of claim 36, wherein the axis of rotation of each of the
openings has an origin, and wherein the origins differ, such that the
shell comprises multiple origins that vary from one another, wherein the
varying angles of the openings comprise normal and non-normal angles with
respect to the inner surface of the shell, such that there are a
plurality of insertion points that the plurality of fasteners are
inserted into at a location where there is adequate bone.

38. The system of claim 37, wherein the axes of rotation of the plurality
of openings are formed at angles with respect to the inner surface of the
shell, wherein the angles diverge from each other.

39. The system of claim 36, wherein the system further comprises a
plurality of spacers having a head; wherein each of the spacers is sized
and shaped for insertion and securement into a vacant opening of the
shell.

40. The system of claim 39, wherein each spacer is inserted from the
inner surface of the shell into a vacant opening of said shell, such that
the head of each spacer is exposed within the inner surface of the shell
to create a mantle of the bonding agent to secure the outer surface of
the bearing insert to the inner surface of the shell.

41. The system of claim 36, wherein the plurality of fasteners and the
plurality of openings are sized and shaped to correspond with each other.

42. The system of claim 41, wherein each of the plurality of openings
comprise a counterbore having a radius; and wherein the plurality of
fasteners each comprise a head having a corresponding radius, such that
each fastener is insertable into bone tissue through a corresponding
opening at multiple, diverging angles with respect to the axis of the
opening.

43. The system of claim 36, wherein the plurality of openings in the
shell range in number between twenty and sixty.

44. The system of claim 36, wherein the inner surface of the shell has a
finish for receiving the bonding agent that is a non-smooth finish
comprising hydroxyapatite.

45. The system of claim 36, wherein the plurality of openings each have a
counterbore having a radius.

46. The system of claim 36, wherein the plurality of openings each have a
diameter, wherein the diameters vary from opening to opening.

47. The system of claim 36, wherein the outer surface of the bearing
insert has a finish for receiving bonding agent that is a non-smooth
finish comprising hydroxyapatite.

48. The system of claim 36, wherein the inner surface of the bearing
insert is configured and dimensioned for receiving a femoral head of a
femoral component therein.

49. The system of claim 46, wherein the fasteners comprise diameters that
are sized and shaped to correspond with the size and shape of diameters
of the openings of the shell.

50. The system of claim 36, wherein the fasteners have diameters within a
range of about 2.7 millimeters to about 6.5 millimeters; and wherein the
fasteners have a length that is within a range of about twenty to
forty-five millimeters, such that the plurality of fasteners operate
together to spread load over a large area of bone tissue to reduce stress
concentration in any one area.

51. The system of claim 39, wherein the spacers are manufactured from the
same material as the bonding agent.

52. The system of claim 40, wherein the mantle that is created is of a
substantially even thickness, which corresponds to a thickness of the
exposed heads of the spacers.

53. The system of claim 39, wherein each of the spacers is secured within
a corresponding opening of the shell via an interlocking mechanism.

54. The system of claim 53, wherein the interlocking mechanism is a press
fit, a screw fit, or an expandable ring.

55. An orthopedic implant for securing to a bone, comprising: a shell
comprising an outer surface configured to contact bone tissue, an inner
surface, and a plurality of openings each of which has an axis; wherein
each of the axes comprises an angle that is formed with respect to a line
that is tangent to a curvature of the inner surface of the shell at the
opening; wherein the each of the axes are formed at divergent angles with
respect to each other; and a plurality of fasteners, wherein each faster
is insertable through one of the openings and into bone tissue at varying
divergent angles in a splayed manner to distribute and transfer forces
placed on the shell to the bone tissue at multiple, varying angles and
over a larger area of the bone.

56. The orthopedic implant of claim 55, wherein each of the axes has a
different origin with respect to another opening, such that the openings
comprise multiple and varying origins; and wherein the angles of the axes
comprise at least one normal angle and at least one non-normal angle with
respect to the line tangent to the curvature of the inner surface of the
shell, such that there are a plurality of insertion points that the
plurality of fasteners are inserted into at a location where there is
adequate bone.

57. The orthopedic implant of claim 55, wherein the system further
comprises a plurality of spacers having a head; wherein each of the
spacers is sized and shaped for insertion and securement into a vacant
opening of the shell.

58. The orthopedic implant of claim 57, wherein each spacer is inserted
from the inner surface of the shell into a vacant opening of said shell,
such that the head of each spacer is exposed within the inner surface of
the shell to create a mantle of a bonding agent.

59. The orthopedic implant of claim 55, wherein the plurality of
fasteners and the plurality of openings are sized and shaped to
correspond with each other.

60. The orthopedic implant of claim 59, wherein each of the plurality of
openings comprise a counterbore having a radius; and wherein the
plurality of fasteners each comprise a head having a corresponding
radius, such that each fastener is insertable into bone tissue through a
corresponding opening at multiple, diverging angles with respect to the
axis of the opening.

61. The orthopedic implant of claim 55, wherein the plurality of openings
in the shell range in number between twenty and sixty.

62. The orthopedic implant of claim 55, wherein the inner surface of the
shell has a finish for receiving a bonding agent, wherein the finish is a
non-smooth finish comprising hydroxyapatite.

63. The orthopedic implant of claim 55, wherein the plurality of openings
each have a counterbore having a radius.

64. The orthopedic implant of claim 55, wherein the plurality of openings
each have a diameter, wherein the diameters vary from opening to opening.

65. The orthopedic implant of claim 55, wherein the system further
comprises a bearing insert having an outer surface; wherein the outer
surface of the bearing insert has a finish for receiving a bonding agent,
wherein the finish is a non-smooth finish comprising hydroxyapatite.

66. The orthopedic implant of claim 65, wherein the inner surface of the
bearing insert is configured and dimensioned for receiving a femoral head
of a femoral component therein.

67. The orthopedic implant of claim 64, wherein the fasteners comprise
diameters that are sized and shaped to correspond with the size and shape
of diameters of the openings of the shell.

68. The orthopedic implant of claim 55, wherein the fasteners have
diameters within a range of about 2.7 millimeters to about 6.5
millimeters; and wherein the fasteners have a length that is within a
range of about twenty to about forty-five millimeters, such that the
plurality of fasteners operate together to spread load over a large area
of bone tissue to reduce stress concentration in any one area.

69. The orthopedic implant of claim 58, wherein the spacers are
manufactured from the same material as the bonding agent.

70. The orthopedic implant of claim 58, wherein the mantle that is
created is of a substantially even thickness, which corresponds to a
thickness of the exposed heads of the spacers.

71. The orthopedic implant of claim 57, wherein each of the spacers is
secured within a corresponding opening of the shell via an interlocking
mechanism.

72. The orthopedic implant of claim 71, wherein the interlocking
mechanism is a press fit, a screw fit, or an expandable ring.

73. A method of securing an orthopedic implant to a bone, comprises:
preparing the bone to receive a shell, wherein the shell comprises a
plurality of openings each of which is defined by a sidewall, wherein
each sidewall is formed at an angle with respect to an inner surface of
said shell, and wherein the sidewalls of the openings are formed at
divergent angles with respect to each other; inserting a plurality of
fasteners into the bone, wherein each fastener is inserted through one of
the openings and into the bone; applying a bonding agent to a prepared
outer surface of a bearing insert; securing the bearing insert to the
shell with the bonding agent, such that the bearing insert is located in
a position for joint stability and reconstruction; wherein the bearing
insert is positioned at a different angle than the shell interfacing the
bone.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part of co-pending U.S.
patent application Ser. No. 13/189,448, filed Jul. 22, 2011, entitled
"LOW STRESS MULTIPLE FIXATION ACETABULAR COMPONENT," which itself is a
continuation of and claims priority to U.S. patent application Ser. No.
13/045,447, filed Mar. 10, 2011, entitled "LOW STRESS MULTIPLE FIXATION
ACETABULAR COMPONENT," which itself claims the benefit of U.S.
Provisional Application No. 61/312,650, filed Mar. 10, 2010, all of which
are hereby incorporated by reference herein in their entireties,
including but not limited to those portions that specifically appear
hereinafter, the incorporation by reference being made with the following
exception: In the event that any portion of any of the above-referenced
applications is inconsistent with this application, this application
supercedes said above-referenced applications.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not Applicable.

BACKGROUND

[0003] 1. The Field of the Disclosure.

[0004] The disclosure relates generally to artificial joint prostheses and
orthopedic implants, and more particularly, but not necessarily entirely,
to acetabular prostheses used in hip joint replacement surgeries and
revision surgeries.

[0005] 2. Description of Related Art

[0006] Total hip joint replacements comprise a femoral component and an
acetabular component. The femoral component is implanted in the patient's
femur and the acetabular component is implanted in the acetabular cavity
in the patient's pelvis. The normal acetabular cavity is generally
spherically shaped. Accordingly, as illustrated in FIG. 1, during initial
hip joint replacement, a spherically-shaped cavity 10 is prepared in the
pelvis 14 for the great majority of patients, and the outer surface of
the acetabular prosthesis 12 has a generally spherical shape to fit in
this cavity.

[0007] Over the past several decades, millions of hip joint replacements
have been performed. As time has progressed, a significant number of
these implants have failed due to aseptic loosening of either or both of
the femoral or acetabular components. In the case of the acetabulum, a
loose prosthesis often erodes bone in the direction of the applied forces
during use, i.e., in the superior and posterior directions. This is
particularly true where the loosened prosthesis had been implanted using
bone cement. As a result, during a revision hip joint replacement, the
surgeon often finds that the once spherical cavity in the pelvis has
become elongated in some manner as shown at 16 in FIG. 2. Also, in some
cases, elongated acetabular cavities or other bony defects may be found
for patients undergoing their first hip joint replacement.

[0008] The classical way to deal with the bone defects, such as an
elongated acetabular cavity, has been to fill a portion of the cavity
with a bone graft to recreate, as best as possible, a spherical cavity in
its normal location. As is evident, this approach suffers from a variety
of problems, including availability of bone for the bone graft,
mechanical difficulties of securing the bone graft to the host bone,
failure of the bone graft to provide and maintain long term mechanical
support for the prosthesis, and the hazard of the spread of certain
infectious diseases.

[0009] Bony defects may be treated by using jumbo acetabular cups, oblong
acetabular cups, modular augments that attach the acetabular cup to the
bone or other methods currently available.

[0010] It will be appreciated that a longitudinal axis of the acetabulum
has a natural angle with respect to the midline of a patient. For maximum
fixation or containment, the outer shell of the acetabular component of a
hip implant may be inserted into the acetabulum at an angle of about 50
degrees to about 60 degrees. Surgeons often position the shell at an
angle of about 55 degrees. For joint stability, the preferred angle of
the face of the bearing element in the coronal plane is on the order of
45 degrees or less. Moreover, the greater the elongation of the cavity,
the greater the departure from the preferred orientation. In terms of
function, such a geometry means that the patient will have a
significantly higher likelihood of dislocation during use.

[0011] In addition to the orientation in the coronal plane, the
functionality of the prosthesis is also affected by the orientation of
the face of the bearing element in the transverse plane. In this case,
the angle between the face of the bearing element and the sagittal plane
is on the order of about 15 degrees to about 20 degrees anteverted (note
that the amount of anteversion increases as the angle increases.)

[0012] Due to the curvature of the pelvis and the usual direction of
erosion and elongation, the prior art oblong acetabular prostheses tend
to assume an orientation which is less anteverted or, in some cases, may
even be retroverted. The magnitude of this problem also becomes greater
as the elongation of the cavity becomes greater. Again, in terms of
function, orientations which are less anteverted or are retroverted mean
that the patient will have a higher likelihood of dislocation during use.

[0013] Despite the advantages ofknown hemispherically shaped acetabular
cup systems and devices, improvements are still being sought. However,
the prior art is characterized by several disadvantages that may be
addressed by the disclosure. The disclosure minimizes, and in some
aspects eliminates, these failures, and other problems, by utilizing the
methods and structural features described herein.

[0014] The features and advantages of the disclosure will be set forth in
the description which follows, and in part will be apparent from the
description, or may be learned by the practice of the disclosure without
undue experimentation. The features and advantages of the disclosure may
be realized and obtained by means of the instruments and combinations
particularly pointed out herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The features and advantages of the disclosure will become apparent
from a consideration of the subsequent detailed description presented in
connection with the accompanying drawings in which:

[0016] FIG. 1 is a side, cross-sectional view showing the implantation of
a hemispherically-shaped acetabular cup or shell in an acetabular cavity
of a patient's pelvis;

[0017] FIG. 2 is a side, cross-sectional view showing an acetabular cavity
of a patient's pelvis, which has become elongated;

[0018] FIG. 3 is a bottom view of an embodiment of an acetabular cup or
shell implanted into a patient's pelvis and made in accordance with the
principles of the disclosure;

[0019] FIG. 4 is a perspective view of an embodiment of an acetabular cup
or shell shown in combination with a plurality of fasteners and made in
accordance with the principles of the disclosure;

[0020] FIG. 4A is a cross-sectional view of an embodiment of an acetabular
cup or shell shown in combination with a fastener implanted into a
patient's pelvis and made in accordance with the principles of the
disclosure;

[0021]FIG. 5 is a bottom perspective view of an embodiment of a bearing
insert made in accordance with the principles of the disclosure;

[0022]FIG. 6 is a bottom perspective view of an embodiment of a bearing
insert and an acetabular cup or shell made in accordance with the
principles of the disclosure;

[0023] FIG. 7 is a side view of an embodiment of a bearing insert with
bone cement applied to an external surface thereof and made in accordance
with the principles of the disclosure;

[0024]FIG. 8 is a bottom perspective view of an embodiment of a bearing
insert inserted into an acetabular cup or shell and made in accordance
with the principles of the disclosure;

[0025] FIG. 9 is a perspective view of an embodiment of a bearing insert
inserted into an acetabular cup or shell and made in accordance with the
principles of the disclosure;

[0026] FIG. 10 is an illustration of an x-ray image of an embodiment of
the acetabular cup or shell as described herein fastened to a patient's
acetabulum with a plurality of fasteners;

[0027]FIG. 11 is a bottom view of an embodiment of an acetabular cup or
shell made in accordance with the principles of the disclosure;

[0028]FIG. 12 is a side view of the embodiment of the acetabular cup or
shell of FIG. 11;

[0029]FIG. 13 is a side, cross-sectional view of the acetabular cup or
shell taken along section A-A of FIG. 12;

[0030]FIG. 14 is another side, cross-sectional view of the acetabular cup
or shell taken along section A-A of FIG. 12 illustrating the coating
details of the acetabular cup or shell;

[0031]FIG. 15 is an enlarged, side view of an opening in the acetabular
cup or shell as shown in Detail C of FIG. 13;

[0032]FIG. 16 is a side, partial cross-sectional view of the acetabular
cup or shell taken along section D-D of FIG. 11;

[0033]FIG. 17 is an enlarged, side view of an opening in the acetabular
cup or shell as shown in Detail E of FIG. 13;

[0034] FIG. 18 is a perspective view of an embodiment of an acetabular cup
or shell of the disclosure;

[0035]FIG. 19 is a bottom view of the embodiment of the acetabular cup or
shell illustrated in FIG. 18;

[0036]FIG. 20 is a side, cross-sectional view of the acetabular cup or
shell taken along section F-F of FIG. 19;

[0037]FIG. 21 is a side, cross-sectional view of the acetabular cup or
shell taken along section F-F of FIG. 19 illustrating the coating details
of the acetabular cup or shell;

[0038]FIG. 22 is an enlarged, side view of an opening in the acetabular
cup or shell as shown in Detail H of FIG. 21;

[0039] FIG. 23 is a top view of an embodiment of an acetabular cup or
shell made in accordance with the principles of the disclosure;

[0040] FIG. 24 is a cross-sectional view of the acetabular cup or shell
taken along section A-A of FIG. 23 and made in accordance with the
principles of the disclosure;

[0041] FIG. 24A is a side, cross-sectional view of an embodiment of an
acetabular cup or shell illustrating angles of the acetabular cup or
shell and made in accordance with the principles of the disclosure;

[0042] FIG. 24B is a side, cross-sectional view of an embodiment of an
acetabular cup or shell illustrating angles of the acetabular cup or
shell and made in accordance with the principles of the disclosure;

[0043] FIG. 24C is a side, cross-sectional view of an embodiment of an
acetabular cup or shell illustrating angles of the acetabular cup or
shell and made in accordance with the principles of the disclosure;

[0044] FIG. 24D is a side, cross-sectional view of an embodiment of an
acetabular cup or shell illustrating angles of the acetabular cup or
shell and made in accordance with the principles of the disclosure;

[0045] FIG. 24E is a side, cross-sectional view of an embodiment of an
acetabular cup or shell made in accordance with the principles of the
disclosure;

[0046] FIG. 25 is a side view of the acetabular cup or shell of FIG. 23
made in accordance with the principles of the disclosure;

[0047] FIG. 26 is a perspective view of the acetabular cup or shell taken
from the perspective of B-B in FIG. 24;

[0048] FIG. 27 is an enlarged, side view of a figure eight shaped opening
in the acetabular cup or shell as shown in Detail C of FIG. 26;

[0049]FIG. 28 is a perspective view of an embodiment of an assembly of
the disclosure, including an acetabular cup or shell, a bearing insert,
and a plurality of fasteners made in accordance with the principles of
the disclosure;

[0050] FIG. 29 is an enlarged, side view of an inner surface of the
acetabular cup or shell as shown in Detail B of FIG. 28; and

[0051] FIGS. 30 through 35 illustrate bottom views ofvarious embodiments
of an acetabular cup or shell with openings in various locations and
numbers made in accordance with the principles of the disclosure.

DETAILED DESCRIPTION

[0052] For the purposes of promoting an understanding of the principles in
accordance with the disclosure, reference will now be made to the
embodiments illustrated in the drawings and specific language will be
used to describe the same. It will nevertheless be understood that no
limitation of the scope of the disclosure is thereby intended. Any
alterations and further modifications of the inventive features
illustrated herein, and any additional applications of the principles of
the disclosure as illustrated herein, which would normally occur to one
skilled in the relevant art and having possession of this disclosure, are
to be considered within the scope of the disclosure.

[0053] Before the system, method and devices for improving stability and
fixation in an acetabular cup when there is less than optimal amount of
bone to secure the acetabular cup to the acetabulum, whether used in a
revision or total hip arthroplasty, are disclosed and described, it is to
be understood that this disclosure is not limited to the particular
configurations, process steps, and materials disclosed herein as such
configurations, process steps, and materials may vary somewhat. It is
also to be understood that the terminology employed herein is used for
the purpose of describing particular embodiments only and is not intended
to be limiting since the scope of the disclosure will be limited only by
the appended claims, if any, and equivalents thereof.

[0054] In describing and claiming the disclosure, the following
terminology will be used in accordance with the definitions set out
below.

[0055] It must be noted that, as used in this specification and the
appended claims, the singular forms "a," "an," and "the" include plural
referents unless the context clearly dictates otherwise.

[0056] As used herein, the terms "comprising," "including," "containing,"
"characterized by," and grammatical equivalents thereof are inclusive or
open-ended terms that do not exclude additional, unrecited elements or
method steps.

[0057] As used herein, the term "proximal" shall refer broadly to the
concept of a nearest portion or a portion nearest the midline.

[0058] As used herein, the term "distal" shall generally refer to the
opposite of proximal, and thus to the concept of a further portion, or a
portion furthest from the midline, depending upon the context.

[0059] Referring now to FIGS. 3 and 4, there is illustrated an embodiment
of an acetabular cup or shell 100 made in accordance with the principles
of the disclosure. The acetabular cup 100 may be hemispherically shaped
or may be any other shape to correspond with the shape of the acetabulum,
whether the acetabulum is hemispherically shaped or otherwise deformed in
some respect. It will be appreciated that the acetabulum may comprise a
defect caused by forces placed thereon or a lack of force placed thereon.
One of the most common acetabular cup shapes is the hemispherical cup.
Surgeons are well acquainted with this type of hemispherical cup.
However, in some cases, such as a revision or a total hip arthroplasty
with a defect in the bone, where there is not enough bone to create a
tight press fit or otherwise secure the acetabular cup to the bone,
another option must be used other than the traditional hemispherical cup.

[0060] This disclosure relates to those situations in which it is
difficult for a surgeon to secure or fix the acetabular cup or shell 100
to the bone due, for whatever reason, to bone loss or other defect.
Accordingly, an embodiment of a system for securing an acetabular cup or
shell 100 to the acetabulum may comprise an acetabular cup or shell 100
itself as illustrated in FIGS. 3 and 4, a bearing insert 200 (illustrated
best in FIGS. 5-10) for receiving a femoral head component and a
plurality of spacers 300 for creating a cement mantle as described below
in more detail.

[0061] Referring to FIGS. 3 through 4A, the cup or shell 100 may comprise
a plurality of openings or fenestrations 110 for allowing a fastener 120
to pass therethrough and into the bone. The cup or shell 100 may comprise
a first, inner surface 102 and a second, outer surface 104.

[0062] The first surface 102 of the cup or shell 100 may comprise a face
103 that has a finish that is porous or that has a matte finish to permit
a bonding agent, such as bone cement, to bond thereto. It will be
appreciated that the first surface 102 may be comprised of any non-smooth
finish or a rough finish for receiving bone cement without departing from
the scope of the disclosure. For example, the first surface 102 may
comprise a hydroxyapatite (HA) finish, which is a basic mineral
containing calcium and phosphorus and contributes to the strength of
bone. Hydroxyapatite may be a beneficial material for increasing the
interdigitation between the bonding agent and the first surface 102,
which may permit increased interdigitation between components that may be
bonded together with a bonding agent since hydroxyapatite is a component
of bone tissue.

[0063] The openings 110 may be formed through the first and second
surfaces 102 and 104. It will be appreciated that while the number of
openings 110 need not be an exact number, there may be between about
thirty and sixty openings 110. Further, the plurality of openings 110 may
be located in a pattern across the entire surface of the acetabular cup
or shell 100. However, it will be appreciated that the plurality of
openings 110 may also be randomly positioned across the entire surface of
the acetabular cup or shell 100.

[0064] Each opening 110 may be defined by a sidewall 112. Each opening 110
may have the same or a different size diameter "D" that may range from
very small to very large and may correspond with the diameter of a
corresponding fastener 120. The diameters "D" of the openings 110 may be
between a range of about 2.7 millimeters to about 6.5 millimeters to
accommodate corresponding fasteners 120. It will be appreciated that the
diameter "D" of the openings 110 may be any size, such that the diameters
"D" correspond directly with the diameter size of the fastener 120 to be
inserted therein, such that the diameter size may be larger or smaller
than the diameters that fall within the above range.

[0065] Referring now to FIG. 4A, each of the sidewalls 112 may comprise or
may be formed at an angle, which may be the same as or differ from other
closely located or situated openings 110. The openings 110 may comprise
multiple origins 130 that vary, in which case the sidewalls 112 will be
formed at varying angles. In other words, the sidewalls 112 may not all
be normal to the inner surface 102 of the cup 100. Alternatively, the
plurality of openings 110 may comprise a single origin 130, in which case
the openings may be formed or oriented normal to the surface of the
acetabular cup or shell 100. Each of the openings 110 may comprise a
different origin. It will be appreciated that the origins may fall within
a predetermined area that may extend outwardly from the origin 130a of
the acetabular cup 100.

[0066] The varying angles of each of the sidewalls 112 defining the
openings 110 creates the ability for a surgeon to insert fasteners 120
into bony areas at any desired angle to cause fixation to the acetabulum.
Further, these varying angles may be divergent so as to create a series
of diverging angles. When a series of fasteners 120 is located in a
corresponding series of openings 110, i.e., in an area where there is
bone to accept or receive fasteners 120, the fasteners 120 are then
secured in the bone at diverging angles. The result of the diverging
angles at which the fasteners 120 are inserted is maximum fixation and
security within the bone.

[0067] Further, because the openings 110 may be located across the entire
surface of the acetabular cup or shell 100, there are multiple or a
plurality of insertion points, such that fasteners 120 may be inserted
into any location where there is adequate bone. The multiple insertion
points for the fasteners 120 and the divergent angles (created by the
sidewalls 112 defining openings 110) at which the fasteners 120 may be
inserted into the bone allows the fasteners 120 to adequately grip the
bone at various and multiple locations. The result of the gripping is
that forces and stresses experienced in the hip joint may be spread over
a larger area of the pelvic bone, thus providing maximum fixation and
securement of the shell or cup 100.

[0068] It will be appreciated that the fasteners 120 may be screws, nails,
pins, or any other fastener that may be known or that may become known in
the future without departing from the scope of the disclosure. The
fasteners 120 may correspond in diameter to the diameters "D" of the
openings 110 in the acetabular cup or shell 100. The fasteners 120 may
comprise relatively small diameters as well as other more traditional
sizes. For example, the fasteners may have a 2.7 millimeter diameter and
may be about twenty to thirty-five millimeters in length or the diameters
may be larger and more traditional, such as a 6.5 millimeter diameter
with a length between about forty to forty-five millimeters in length.

[0069] In an embodiment, the plurality of fasteners that may be inserted
into the bone may comprise an average diameter that is between a range of
about three millimeters to about five millimeters and an average fastener
length that is between a range of about twenty-five millimeters to about
thirty-five millimeters in length.

[0070] It will be appreciated that in an embodiment, the shell may
comprise a certain number of openings or throughbores per concentration
area of the shell. That certain number of openings may be uniform across
the entire outer surface of the shell. As used herein the phrase
"concentration area" refers to a portion of the total surface area of the
outer surface of the shell measured in millimeters squared. In an
embodiment, the plurality of openings may comprise about five to about
fifteen openings per concentration area of the outer surface of the
shell, which per unit surface area may be between a range of about eighty
square millimeters to about one-hundred and seventy-five square
millimeters.

[0071] It will be appreciated that the use of a plurality or multiple
small diameter fasteners 120 may operate to spread the load over a larger
area from the acetabular cup or shell 100 to the bone and thereby reduce
stress concentration in any one area. For example, in an area where bone
contact with the acetabular cup or shell 100 is less than optimal,
locating a plurality of smaller diameter fasteners 120 in an acetabular
cup or shell 100 having a plurality of openings 110 will operate to
transmit forces from the acetabular cup or shell 100 through to the
fasteners 120 and ultimately to the bone. For example, the acetabular cup
or shell 100 may have a plurality of openings 110 between a range of
about twenty to about sixty, or a range of about thirty to about fifty,
wherein each opening 110 has a diverging angle and a smaller diameter to
accept smaller fasteners 120.

[0072] Referring to FIGS. 5 through 10, a bearing insert 200 is
illustrated and will now be discussed. The bearing insert 200 may be
manufactured from any suitable material that is known or that may become
known in the art for use within a patient's body. Such materials may
comprise polyethylene, any suitable metallic material or alloy, ceramic,
diamond, or any other suitable material or combination of materials for
use as a bearing insert. It will be appreciated that the choice of
material is dependent upon the surgeon and the desired result or
application. The system of the disclosure allows a surgeon more selection
and freedom to select a desired material for the insert 200 and the
surgeon is not dependent upon a pre-manufactured kit or insert, including
whatever mechanical lock feature that may be used to secure the insert
200 to the cup or shell 100. Thus, the disclosure contemplates allowing
the surgeon to utilize any desired bearing insert 200 made of any
suitable material without regard to any mechanical attachment to the
acetabular cup or shell 100.

[0073] Referring specifically to FIGS. 5, 7 and 8, the disclosure may
utilize a fixation material or bonding agent, such as bone cement 250, to
bond the bearing insert 200 to the acetabular cup or shell 100 as the
attachment mechanism between the bearing insert 200 and shell 100. It
will be appreciated that the bone cement 250 may be any bonding agent or
material used in the art or that may be used in the future in the art
without departing from the scope of the disclosure.

[0074] As illustrated best in FIG. 5, the bearing insert 200 may comprise
an outer surface 210 and an inner surface 220. The outer surface 210 of
the bearing insert 200 may be prepared with a texture or rough finish to
receive or bond to the fixation material or bonding agent 250, such as
bone cement. Accordingly, the outer surface 210 may comprise a non-smooth
surface. In an embodiment, the texture of the outer surface 210 may be a
geometry comprising a plurality of troughs or a grooves 213 or any rough
or textured surface that is other than a smooth surface (illustrated best
in FIG. 5). The roughened or textured outer surface 210 may be anything
greater than microsized pores in order to help the fixation material or
bonding agent, such as bone cement, adhere to the outer surface 210 of
the bearing insert 200, and may be formed as part of or within the outer
surface 210 of said bearing insert 200. Conversely, the inner surface 220
of the bearing insert 200 may be suitable for receiving therein the
femoral head of the femoral component of the hip replacement (illustrated
best in the image of an x-ray in FIG. 10).

[0075] For example, during use, the bone cement 250 may be placed on the
outer surface 210 of the bearing insert 200. After the bone cement is
applied to the bearing insert 200, the insert 200 may then be located
within an interior cavity 140 of the acetabular cup or shell 100, such
that the bone cement 250 that is located on the outer surface 210 of the
insert 200 contacts the inner surface 102 of the cup 100 to secure the
insert 200 to the cup or shell 100.

[0076] Referring back specifically to FIG. 4A, an embodiment of the system
for securing an acetabular cup or shell 100 to the acetabulum may
comprise a plurality of spacers 300 for receipt on the inner surface 102
of the acetabular cup 100 and specifically in the openings 110 of the cup
100. The spacers 300 may be attached or secured within the opening 110 in
any manner, including a press fit, screw fit, an expandable ring or any
other interlocking mechanism without departing from the scope of the
disclosure.

[0077] The spacers 300 may be manufactured from the same material as the
fixation material 250 used to attach or secure the bearing insert 200 to
the inner surface 102 of the acetabular cup or shell 100. The spacers 300
may be used to create a mantle, such as a cement mantle, that is
substantially even with respect to the thickness of the spacer's head
302, such that the insert 200 may be secured to the cup or shell 100.
Further, the spacers 300, the heads 122 of the fasteners 120 and the
non-smooth first or inner surface 102 of the acetabular cup 100 creates a
surface that is ready to bond with cement in a manner that is sufficient
to securely attach the bearing insert 200 to the acetabular cup or shell
100.

[0078] The system disclosed herein, permits a surgeon with the ability to
orient the bearing insert 200 separately from the shell or cup 100. In
use, as the bearing insert 200 is being oriented and positioned within
the cavity 140 of the cup or shell 100, the surgeon has the ability to
manipulate the insert 200 to achieve the best position for joint
stability and reconstruction. The best position for locating the insert
200 to create joint stability and reconstruction may be a different
position than the cup or shell 100 interfacing with the bone. Further,
the system disclosed herein may reduce the need or tendency to use bone
grafting material.

[0079] In FIGS. 11 through 22 embodiments of an acetabular cup or shell
400 are illustrated and will now be discussed. The acetabular cups or
shells of FIGS. 11 through 22 may comprise the same or similar
characteristics and features described above in connection with the
various embodiments of the acetabular cup or shell 100 and illustrated in
FIGS. 3 and 4. The following description will concentrate on the
characteristics and features that have not been previously described
above in connection with the various embodiments of the acetabular cup or
shell 100 illustrated in FIGS. 3 and 4.

[0080] Referring to FIGS. 11 through 22, the acetabular cup or shell 400
may comprise an inner surface 402 prepared with a textured finish for
receiving the bonding agent, an outer surface 404 configured to contact
bone tissue, and a plurality of openings 410. Each of the openings 410
may be defined by an axis of rotation R-R (illustrated best in FIG. 22)
and a sidewall 412. The axis of rotation R-R of each of the openings 410
may have differing origins, such that the plurality of openings 410 may
comprise multiple origins that vary from one another. The openings 410
may comprise multiple origins 430 that vary, in which case the sidewalls
412 will be formed at varying angles (illustrated best in FIG. 4A). In
other words, the sidewalls 412 may not all be oriented normal to the
inner surface 402 of the cup 400. Alternatively, the plurality of
openings 410 may comprise a single origin, in which case the openings may
be oriented normal to the surface of the acetabular cup or shell 400 as
illustrated best in FIGS. 11 through 22.

[0081] In instances in which the axis of rotation R-R of the opening 410
is normal to the inner surface 402 of the shell 400, the axis R-R may
pass through an origin of the shell 400. The origin of the shell may be
the central with respect to a lower lip 450 of the shell 400. It will be
appreciated that some of the openings 410 may comprise an axis of
rotation R-R that is angled with respect to the axis of rotation R-R or
another opening 410 that is normal to the inner surface 402 of the shell
400. Such angles may vary and diverge from one opening to the next
opening to allow the fasteners to be inserted at various angles and
insertion points. Thus, the varying angles of the openings 410 may be
oriented normal and non-normal with respect to the inner surface 402 of
the shell 400, such that there are a plurality of insertion points that
the plurality of fasteners are inserted into at a location where there is
adequate bone.

[0082] Referring specifically to FIG. 22, the plurality of openings 410
may each comprise a counterbore 411. The counterbore 411 may comprise a
radius. As noted above, the fasteners may correspond in shape and size to
the openings 410 of the shell 400. Accordingly, each fastener may
comprise a head having a corresponding radius to the radius of the
counterbore 411, such that each fastener may be insertable into bone
tissue through a corresponding opening 410 at multiple, diverging angles
with respect to the axis R-R of the opening 410.

[0083] It will be appreciated that the openings 410 may be located across
a portion of the acetabular cup or shell 400 or across the entire
acetabular cup or shell 400 as illustrated best in FIGS. 11, 19 and
30-35. As illustrated in FIGS. 11, 19 and 30-35, it will be appreciated
that the openings 410 may be spaced around the surface area of the
acetabular cup or shell 400. The openings 410 may be spaced in arrays or
groups, with each array or group being defined by its proximity to a
central opening 425 of the acetabular cup or shell 400. The openings 410
in the same array or group are all substantially the same distance away
from the central opening 425. For example, the openings 410 in the first
level array or group are the closest in proximity to the central opening
425, the openings 410 in the second level array or group are the next
(second overall) closest in proximity to the central opening 425, the
openings 410 in the third level array or group are the next (third
overall) closest in proximity to the central opening 425 and so forth. It
will be appreciated that there may be one array or group or a plurality
of arrays or groups of openings 410 that are formed within the acetabular
cup or shell 400. For example, there may be one array, two arrays, three
arrays, four arrays or more. As illustrated, the acetabular cup or shell
400 in FIG. 11 has a single array. Whereas, the acetabular cup or shell
400 in FIG. 19 has four arrays.

[0084] Referring to FIGS. 19 and 20, it will be appreciated that the
openings 410 in each array level may comprise their own unique
relationship to other openings 410 in the same array level. The central
opening 425 may comprise a center point through which a central axis A-A
of the acetabular cup or shell 400 may run. Additionally, each opening
410 may also comprise a center point 413, through which the axis of the
individual opening 410 may run. The relationship between each opening 410
in each array level may be characterized by an angle, which may be formed
by the intersection of the two axes at a single origin 130 of the
acetabular cup or shell 400.

[0085] As illustrated best in FIG. 19, angle 610 may be formed by the
intersection (at the origin 130 of the cup or shell 400) of the
respective central axes of two individual openings 410 formed within the
first array level and may between a range of about forty degrees and
about sixty-five degrees, or between a range of about forty-five degrees
and about sixty degrees, or between a range of about fifty degrees to
about fifty-five degrees, such as about fifty-one degrees to about
fifty-two degrees. It will be appreciated that an angle 612 formed by the
intersection (at the origin 130 of the cup or shell 400) of the central
axis of the acetabular cup or shell 400 and a central axis of an opening
410 within the first array level (illustrated best in FIG. 20) may be
between a range of about twenty degrees and about thirty-two degrees, or
between a range of about twenty-two degrees and about thirty degrees, or
between a range of about twenty-three degrees to about twenty-seven
degrees, such as about twenty-four degrees to about twenty-five degrees.

[0086] Additionally, as illustrated best in FIG. 19, angle 620 may be
formed by the intersection (at the origin 130 of the cup or shell 400) of
the respective central axes of two individual openings 410 formed within
the second array level and may between a range of about twenty degrees
and about fifty degrees, or between a range of about twenty-five degrees
and about forty-five degrees, or between a range of about thirty degrees
to about forty degrees, such as about thirty-two degrees to about
thirty-seven degrees. It will be appreciated that an angle 622 formed by
the intersection (at the origin 130 of the cup or shell 400) of the
central axis of the acetabular cup or shell 400 and a central axis of an
opening 410 within the second array level (illustrated best in FIG. 20)
may be between a range of about thirty degrees and about fifty degrees,
or between a range of about thirty-two degrees and about forty-eight
degrees, or between a range of about thirty-five degrees to about
forty-five degrees, such as about forty degrees.

[0087] Additionally, as illustrated best in FIG. 19, angle 630 may be
formed by the intersection (at the origin 130 of the cup or shell 400) of
the respective central axes of two individual openings 410 formed within
the third array level and may between a range of about twenty degrees and
about forty-five degrees, or between a range of about twenty-five degrees
and about forty degrees, or between a range of about thirty degrees to
about thirty-eight degrees, such as about thirty-two degrees to about
thirty-three degrees. It will be appreciated that an angle 632 formed by
the intersection (at the origin 130 of the cup or shell 400) of the
central axis of the acetabular cup or shell 400 and a central axis of an
opening 410 within the third array level (illustrated best in FIG. 20)
may be between a range of about forty degrees and about seventy degrees,
or between a range of about forty-five degrees and about sixty-five
degrees, or between a range of about fifty degrees to about sixty
degrees, such as about fifty-five degrees.

[0088] Further, as illustrated best in FIG. 19, angle 640 may be formed by
the intersection (at the origin 130 of the cup or shell 400) of the
respective central axes of two individual openings 410 formed within the
fourth array level and may between a range of about twenty degrees and
about forty-five degrees, or between a range of about twenty-five degrees
and about forty degrees, or between a range of about thirty degrees to
about thirty-eight degrees, such as about thirty-two degrees to about
thirty-three degrees. It will be appreciated that an angle 642 formed by
the intersection (at the origin 130 of the cup or shell 400) of the
central axis of the acetabular cup or shell 400 and a central axis of an
opening 410 within the fourth array level (illustrated best in FIG. 20)
may be between a range of about fifty-five degrees and about eighty-five
degrees, or between a range of about sixty degrees and about eighty
degrees, or between a range of about sixty-five degrees to about
seventy-five degrees, such as about seventy degrees.

[0089] Referring to FIGS. 11 and 13, angle 650 may be formed by the
intersection (at the origin 130 of the cup or shell 400) of the
respective central axes of two individual openings 410 formed within the
cup or shell 400 and may between a range of about twenty-five degrees and
about forty-five degrees, or between a range of about thirty degrees and
about forty-two degrees, or between a range of about thirty-two degrees
to about forty degrees, such as about thirty-five degrees to about
thirty-eight degrees. It will be appreciated that an angle 652 formed by
the intersection (at the origin 130 of the cup or shell 400) of the
central axis of the acetabular cup or shell 400 and a central axis of an
opening 410, as illustrated best in FIG. 13, may be between a range of
about thirty-five degrees and about sixty-five degrees, or between a
range of about forty degrees and about sixty degrees, or between a range
of about forty-five degrees to about fifty-five degrees, such as about
fifty degrees.

[0090] Referring now to FIGS. 11, 19, 23-35, it will be appreciated that
the hip bone may be comprised of vascular safe zones, which are ideal and
optimal for the placement of fasteners into the bone. The
posterior-superior safe zone of the hip bone is the ideal location for
the placement of fasteners due to the amount of bone present and relative
absence of nuerovascular structures. The placement of fasteners into the
posterior-superior safe zone aids in stabilizing the shell within the
acetabular cavity. Hence, the posterior-superior safe zone is the
best-suited location for inserting fasteners into the hip bone and
results in the lowest risk of implant failure.

[0091] The implant illustrated in FIGS. 23-29 may comprise any combination
or all of the features discussed above in connection with other
embodiments of the shell, fasteners and bearing insert. For the sake of
convenience, only the differences between FIGS. 23-29 and the other
embodiments disclosed herein will be primarily addressed. The implant
illustrated in FIGS. 23-29 may generally comprise a shell 500, fasteners
520a and 520b, and a bearing insert 550.

[0092] The shell 500 may comprise an origin or radiant 501, an inner
surface 502, an outer surface 504 and a plurality of openings 510 formed
through the inner surface 502 and the outer surface 504. The origin or
radiant 501 may be defined as a point located on the central axis A-A of
the shell 500, about which the shell 500 may conceivably rotate such that
the shell may be considered substantially symmetrical with respect to the
axis and origin or radiant 501 as illustrated in FIGS. 23 through 25. The
shell 500 may comprise a spatial concentration of openings 510 that may
be within a range of about five to about fifteen openings per
concentration area of the shell 500, wherein the concentration area is
defined as a surface area of the outer surface 504 of the shell 500 that
may be between a range of about eighty square millimeters to about
one-hundred and seventy-five square millimeters. It will be appreciated
that the concentration area may or may not be the entire surface area of
the outer surface 504 of the shell 500. For example, the spatial
concentration of openings per concentration area may be concentrated into
one or more quadrants of the shell 500 or may be distributed across the
entire surface area of the outer surface 504 of the shell 500 without
departing from the scope of the disclosure.

[0093] The plurality of openings 510 may each be sized, shaped, configured
and dimensioned for receiving a fastener 520 therein. The openings 510
may comprise at least two sizes, a first size opening 514 configured and
dimensioned to receive the first or primary fasteners 520a therein and a
second size opening 516 configured and dimensioned to receive the second
or secondary fasteners 520b therein.

[0094] Referring specifically to FIGS. 24A and 28, the shell 500 may
comprise a plurality of first openings 514 that each have a diameter that
corresponds with the diameter of a first fastener 520a, such that the
first fastener 520a may be inserted thereinto. These first openings 514
may be distributed over the shell 500 in order to target the safe zones
of the hip bone, such as the posterior-superior zone. The first openings
514 may be formed at an angle θ with respect to the central the
axis A-A of the shell 500, which passes through the origin 501. Angle
θ may be within a range of about twenty-five degrees to about forty
degrees in order to receive and position a first fastener in
posterior-superior zone as shown in FIGS. 24A and 28.

[0095] In an embodiment, the first openings 514 may be formed at an angle
with respect to the central axis A-A of the shell 500. In an embodiment
one or more of the first openings 514 may be defined by a sidewall 514a
that may form an acute angle with a line that is tangent to an exterior
surface 504 of the shell 500 and that intersects a central axis H-H of
the first opening 514 defined by the sidewall 514a. The angle may be
within a range of about twenty-five degrees to about forty degrees.

[0096] In an embodiment one or more of the first openings 514 may be
defined by a sidewall 514a that defines a central axis H-H of the first
opening 514 and that may form an acute angle with respect to a line that
may be both tangent to an exterior surface 504 of the shell 500 and that
intersects the central axis H-H of the first opening 514. The angle may
be within a range of about twenty-five degrees to about forty degrees.

[0097] The shell 500 may also comprise a plurality of second openings 516,
which may be smaller than the first openings 514. The second openings 516
may be distributed around the shell 500, whether equally around the
entire four quadrants of the shell 500 or concentrated in one or more
particular quadrants of the shell 500 (illustrated best in FIGS. 30-35),
such that when the second fasteners 520b are inserted thereinto the
second fasteners are insertable into the bone in a variety of directions
and at diverging angles. In an embodiment, the axis of the second
openings 516 may be normal or perpendicular to the tangent of the curve
of the inner surface 502 or outer surface 504 of the shell 500. In an
embodiment, the second openings 516 may have diverging angles, where the
central axis J-J of the second opening 516 may be formed at an angle with
respect to the central axis A-A of the shell 500 that passes through the
origin 501, wherein the angle may vary between about twenty degrees to
about eighty degrees as shown in FIG. 24A.

[0098] In an embodiment, the second openings 516 may be formed at an angle
with respect to the central axis A-A of the shell 500. In an embodiment,
one or more of the second openings 516 may be defined by a sidewall 516a
that may form an acute angle with a line that is tangent to an exterior
surface 504 of the shell 500 and that may intersect the central axis J-J
of the second opening 516 defined by the sidewall 516a.

[0099] In an embodiment one or more of the second openings 516 may be
defined by a sidewall 516a that defines the central axis J-J of the
second opening 516 and that may form an acute angle with a line that is
both tangent to an exterior surface 504 of the shell 500 and that
intersects the central axis J-J.

[0100] Referring now to FIG. 24A, in an embodiment, one or more of the
plurality of openings, whether first openings 514 or second openings 516,
may be defined by a sidewall 514a or 516a that may form an acute angle
(600 or 602) with a line (b-b or c-c) that is tangent to an exterior
surface 504 of the shell 500 and that may intersect a central axis H-H or
J-J of the opening 514 or 516 defined by the sidewall 514a or 516a.

[0101] Referring now to FIG. 24B, in an embodiment, one or more of the
plurality of openings, whether first openings 514 or second openings 516,
may be defined by a sidewall 514a or 516a that defines a central axis H-H
or J-J of the opening 514 or 516, which central axis H-H or J-J may form
a right angle or an acute angle (604 or 606) with a line (b-b or c-c)
that is both tangent to an exterior surface 504 of the shell 500 and that
may intersect the central axis H-H or J-J of the opening 514 or 516.

[0102] Referring now to FIG. 24C, in an embodiment, one or more of the
plurality of openings, whether first openings 514 or second openings 516,
may be defined by a sidewall 514a or 516a that may form an acute angle
(608 or 610) with an imaginary line (K-K or L-L) that is perpendicular to
a tangent line (b-b or c-c) of an exterior surface 504 of the shell 500,
wherein the tangent line (b-b or c-c) intersects a central axis H-H or
J-J of the opening 514 or 516 defined by the sidewall 514a or 516a. It
will be appreciated that the imaginary line may be co-axial with respect
to the central axis H-H or J-J of the opening 514 or 516.

[0103] Referring now to FIG. 24D, in an embodiment, one or more of the
plurality of openings, whether first openings 514 or second openings 516,
may be defined by a sidewall 514a or 516a that defines a central axis H-H
or J-J of the opening 514 or 516, which central axis H-H or J-J may form
an acute angle (612 or 614) with an imaginary line (K-K or L-L) that is
perpendicular to a line (b-b or c-c) that is both tangent to an exterior
surface 504 of the shell 500 and that intersects the central axis H-H or
J-J of the opening 514 or 516.

[0104] Referring now to FIG. 24E, in an embodiment, one or more of the
plurality of openings, whether first openings 514 or second openings 516,
may be defined by a sidewall 514a or 516a that defines a central axis H-H
or J-J of the opening 514 or 516. The sidewall 514a or 516a may include a
first opposing side-line 514a1 or 516a1 and a second opposing side-line
514a2 or 516a2. The first opposing side-line (514a1 or 516a1) and the
second opposing sideline (514a2 or 516a2), respectively, may reside on
opposing sides of the central axis H-H or J-J of the opening 514 or 516,
such that each sideline 514a1, 514a2 or 516a1, 516a2 progresses toward
the central axis H-H or J-J of the opening 514 or 516 in an
interior-to-exterior direction (e.g., progresses from the interior
surface 502 toward the exterior surface 504) with respect to the shell
500, such that the entrance to the opening at the interior portion of the
shell is larger than the exit to the opening at the exterior portion of
the shell.

[0105] It will be appreciated that the central axis H-H or J-J of the
opening 514 or 516 may be defined as extending through the center of the
opening 514 or 516. For example, in the case of an opening that may be
cylindrical or circular in shape, the central axis extends through the
center point of the cylinder or circle, which center point may be defined
by the radius of the cylinder or circle, such that the central axis
passes through the center of the opening.

[0106] Referring now to FIGS. 23-27, it will be appreciated that the rim
area of the shell 500 may be an area where diverging openings may be
particularly useful. Further, it will be appreciated that an embodiment
may comprise one or more figure 8 (eight) shaped openings 515, where the
opening 515 is defined by the overlapping circumference of two openings
as illustrated best in FIGS. 23-27. The figure 8 shape may be used in a
substantially hemispherical shell and may provide a surgeon with the
ability to insert fasteners 520a or 520b at different and varying angles
in order to locate fasteners 520 as securely as possible in the bone,
depending upon bone anatomy of the patient, during a procedure.

[0107] Referring specifically now to FIG. 28, the plurality of first
fasteners 520a may each have a diameter that is greater than or equal to
about 6.0 millimeters. For example, in an embodiment the diameter of the
first fastener 520a may be about 6.5 millimeters. The number of first
fasteners 520a used in a case may change depending upon the amount and
location of available bone. Thus, the number of first fasteners 520a used
in a given case may be within a range of about two to about six
fasteners. The length of the first fasteners 520a may be within a range
of about thirty millimeters to about forty-five millimeters or longer
without departing from the scope of the disclosure. These larger
fasteners, which may be screws or pins or other fasteners to secure an
implant to bone, may be used to provide stability within the bone. These
larger, first fasteners 520a may be used to locate and secure the shell
in the posterior-superior safe zone of the hip bone.

[0108] Conversely, the plurality of second fasteners 520b may each have a
diameter that is less than or equal to 3.5 millimeters for securing said
shell to bone tissue. The second fasteners 520b may be inserted into any
location where there is adequate bone available and is not dependent upon
a large amount of bone due to their smaller size. The second fasteners
520b may be inserted in a bony area that may be viewed as deficient or
otherwise inadequate to receive the larger, first fasteners 520a. For
example, in an embodiment the diameter of the second fastener 520b may be
about 2.7 millimeters.

[0109] The number of second fasteners 520b used in a given case may change
depending upon the amount and location of available bone. In most
situations, the larger number of second fasteners 520b used the more
fixation points there will be to secure the shell 500 to the bone, such
that forces may be distributed through each fixation point to the bone.
Thus, the number of second fasteners 520b used in a given case may be at
least twelve in number and may be within a range of about twelve to about
thirty or more in number.

[0110] In an embodiment, the plurality of second fasteners 520b may be at
least twelve fasteners in number. In an embodiment, the plurality of
second fasteners 520b may be at least fifteen fasteners in number. In an
embodiment, the plurality of second fasteners 520b may be at least twenty
fasteners in number. In an embodiment, the plurality of second fasteners
520b may be at least twenty-five fasteners in number. In an embodiment,
the plurality of second fasteners 520b may be at least thirty fasteners
in number. In an embodiment, the plurality of second fasteners 520b may
be at least thirty-five fasteners in number. In an embodiment, the
plurality of second fasteners 520b may be at least forty fasteners in
number. In an embodiment, the plurality of second fasteners 520b may be
at least forty-five fasteners in number. In an embodiment, the plurality
of second fasteners 520b may be at least fifty fasteners in number. In an
embodiment, the plurality of second fasteners 520b may be at least
fifty-five fasteners in number. In an embodiment, the plurality of second
fasteners 520b may be about fifteen fasteners to about sixty fasteners in
number.

[0111] It will be appreciated that the number of first and second
fasteners 520b may be dependent on the bone quality and whether and to
what extent there is bone deficiency. The number of second fasteners 520b
may increase to provide added stability and load transfer. The more
unstable the bone is, the more important it is to locate as many second
fasteners 520b as possible into that bone, since the larger first
fasteners 520a may be more difficult to secure to that deficient bone.
The disclosure contemplates using as many secondary fasteners 520b as
possible to provide as many fixation points as possible, no matter what
the quality of the bone is. As the number of second fasteners 520b
secured to bone increases, the more fixation points there are, which
results in providing added stability and load distribution through those
fixation points. The result may be an even distribution of force placed
on the implant and a longer implant life.

[0112] It will be appreciated that each of the plurality of second
fasteners 520b may comprise a length that is less than thirty
millimeters, and may be between about twenty millimeters to about
twenty-five millimeters in length. Thus, the length of the second
fasteners 520b may be less than the average length of an acetabular screw
or pin, which is typically within a range of about thirty-five to
forty-five millimeters.

[0113] It will be appreciated that each of the plurality of first
fasteners 520a and the plurality of second fasteners 520b may be
insertable through one of the first or second openings 514 and 516,
respectively, of the shell 500 and into the bone at an angle with respect
to the origin of said shell 500. The result is to distribute and transfer
forces placed on shell 500 to the bone at multiple, varying insertion
points, which correspond with the fastener 520 inserted into the bone.

[0114] Referring to FIGS. 28 and 29, the inner surface 502 of the shell
500 may be textured or otherwise prepared for receiving the fixation
material or bonding agent, such as bone cement. In an embodiment, the
texture of the inner surface 502 may be a geometry comprising a plurality
of troughs or a grooves 503 or any rough or textured surface that is
other than a smooth surface (illustrated best in FIG. 29). The roughened
or textured inner surface 502 may be anything greater than microsized
pores in order to help the fixation material or bonding agent, such as
bone cement, adhere to the inner surface 502 of the shell 500, and may be
formed as part of or within the inner surface 502 of the shell 500.

[0115] Those having ordinary skill in the relevant art will appreciate the
advantages provided by the features of the disclosure. For example, it is
a potential feature to provide a low stress, multiple fixation acetabular
component for use in surgical situations where there is inadequate bone
for traditional fixation. It is another potential feature to use multiple
fasteners that may be inserted into the bone at diverging angles to
provide maximum fixation in the bone. It is another potential feature to
insert about twelve to about sixty fasteners into the bone at diverging
angles. It is another potential feature to provide a plurality of
openings or holes in an acetabular component at diverging angles to
thereby permit a plurality of fasteners having a length that is less than
thirty millimeters, and may be between about twenty millimeters to about
twenty-five millimeters, in length to be inserted therethrough. It is
another potential feature to provide an acetabular component that
distributes stress over a larger area than traditional methods, resulting
in less stress due to the number of fasteners inserted into the bone. It
is another potential feature to provide an acetabular component with
multiple fixation angles.

[0116] In the foregoing Detailed Description, various features of the
disclosure are grouped together in a single embodiment for the purpose of
streamlining the disclosure. This method of disclosure is not to be
interpreted as reflecting an intention that the claimed disclosure
requires more features than are expressly recited in each claim. Rather,
inventive aspects lie in less than all features of a single foregoing
disclosed embodiment.

[0117] It is to be understood that the above-described arrangements are
only illustrative of the application of the principles of the disclosure.
Numerous modifications and alternative arrangements may be devised by
those skilled in the art without departing from the spirit and scope of
the disclosure and the disclosure is intended to cover such modifications
and arrangements. Thus, while the disclosure has been shown in the
drawings and described above with particularity and detail, it will be
apparent to those of ordinary skill in the art that numerous
modifications, including, but not limited to, variations in size,
materials, shape, form, function and manner of operation, assembly and
use may be made without departing from the principles and concepts set
forth herein.